Portal:Energy
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The Energy Portal
Introduction.jpg) The Sun is the source of energy for most of life on Earth. As a star, the Sun is heated to high temperatures by the conversion of nuclear binding energy due to the fusion of hydrogen in its core. This energy is ultimately transferred (released) into space mainly in the form of radiant (light) energy. In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The SI unit of energy is the joule, which is the energy transferred to an object by the work of moving it a distance of 1 metre against a force of 1 newton. Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object's position in a force field (gravitational, electric or magnetic), the elastic energy stored by stretching solid objects, the chemical energy released when a fuel burns, the radiant energy carried by light, and the thermal energy due to an object's temperature. Mass and energy are closely related. Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy. For example, after heating an object, its increase in energy could be measured as a small increase in mass, with a sensitive enough scale. Living organisms require energy to stay alive, such as the energy humans get from food. Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The processes of Earth's climate and ecosystem are driven by the radiant energy Earth receives from the sun and the geothermal energy contained within the earth. Selected article
Nuclear (fission) power stations, provided 11% of the world's electricity in 2012, somewhat less than that generated by hydro-electric stations at 16%. Nuclear energy policy differs between countries, and some countries have no active nuclear power stations, or have phased them out. The first nuclear generated electricity, used to power four 200-watt light bulbs, was produced at the EBR-I reactor near Arco, Idaho, in 1951. This was followed in 1954 by the first grid-connected plant (in the USSR), and in 1956 by the first commercial plant (in the United Kingdom). During the last decades of the 20th century, concerns about nuclear waste, nuclear accidents, radiation and nuclear proliferation led to an anti-nuclear movement. The 1979 Three Mile Island accident, the 1986 Chernobyl disaster, and the 2011 Fukushima disaster also played a part in stopping new plants in many countries, while the economics of nuclear generation and of nuclear decommissioning have also been factors. Despite this, some countries including China and India have continued to remain active in developing nuclear power, Germany will close its 19 nuclear plants by 2020, and is investing heavily in renewable energy commercialization instead. Read more... Selected image Photo credit: From an image by Contributor
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Rockefeller founded the Standard Oil Company in 1870 and ran it until he retired in the late 1890s. He continued to retain his stock and his title as president until 1911, when the company was broken up for carrying out illegal monopoly practices. The new companies formed included the predecessors of Conoco, Amoco, Chevron, Esso, Mobil and Sohio. Rockefeller, who had rarely sold shares, owned stock in all of them. As gasoline had grown in importance his wealth had soared and he became the world's richest man and the first billionaire. Rockefeller's fortune was used to create the modern systematic approach of targeted philanthropy with foundations that had a major impact on medicine, education, and scientific research. His foundations pioneered the development of medical research, and was instrumental in the eradication of hookworm and yellow fever. At his death, at the age of 98, Rockefeller's remaining fortune was estimated at $1.4 billion. As a percentage of the United States economy, no other American fortune has ever come close. Read more... In the news
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